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Nitro-PAH exposures of occupationally-exposed traffic workers and associated urinary 1-nitropyrene metabolite concentrations

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Journal of Environmental Sciences 2016年第11期28卷 213-221页

作者： Justin P.Miller-Schulze Michael Paulsen Takayuki Kameda Akira Toriba Kazuichi Hayakawa Brandon Cassidy Luke Naeher Manuel Aguilar Villalobos christopher d.Simpson department of Chemistry University of Washington WA 98195-1700 USA. department of Environmental and Occupational Health Sciences University of Washington WA 98195 Seattle USA Laboratory of Hygienic Chemistry Instkute of Medical Pharmaceutical and Health Sciences Faculty of Pharmacy Kanazawa UniversityKakurna-machi Kanazawa Ishikawa 920-1192 Japan Graduate School of Natural Science and Technology Kanazawa University Kakma-machi Kanazawa Ishikawa 920-1192 Japan department of Enuironmental Health Sciences University of Georgia Athens CA 30602-2102 USA Asociacion del Aire Ambiental Lima Peru

The assessment of occupational exposure to diesel exhaust（dE） is important from an epidemiological perspective. Urinary biomarkers of exposure have been proposed as a novel approach for measuring exposure to dE. In this study, we measured the concentrations of two urinary metabolites of 1-nitropyrene（1NP）, a nitrated polycyclic aromatic hydrocarbon that has been suggested as a molecular marker of diesel particulate matter. These two metabolites, 6-hydroxy-1-nitropyrene and 8-hydroxy-1-nitropyrene, were determined in urine samples（10 m L） from a small group of workers who were occupationally-exposed to vehicle exhaust in Trujillo, Peru, before and after their workshifts. Workshift exposures to1 NP, as well as PM_（2.5）, 2-nitropyrene and 2-nitrofluoranthene, were also *** to 1NP were similar in all studied workers, averaging 105 ± 57.9 pg/m^3（±standard deviation）. Median urinary concentrations of the average of the pre- and post-exposure samples for 6-hydroxy-1-nitropyrene and 8-hydroxy-1-nitropyrene, were found to be 3.9 and 2.3 pg metabolite/mg creatinine, respectively in the group of occupationally-exposed subjects（n = 17） studied. A direct relationship between workshift exposure to 1NP and urinary 1NP metabolites concentrations was not observed. However,the 1NP exposures and the creatinine-corrected urinary concentrations of the hydroxynitropyrene metabolites in these Peruvian traffic workers were similar to occupationally-exposed taxi drivers in Shenyang, China, and were higher than biomarker levels in office workers from Trujillo without occupational exposure to vehicle *** study provides further evidence that urinary metabolites of 1NP are associated with exposure to dE and may serve as a useful exposure biomarker.

关键词： Urinary biomarkers 1-Nitropyrene diesel particulate matter

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Investigation into a practical approach and application of cotton fiber elongation

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Journal of Cotton Research 2023年第1期6卷 13-24页

作者： dELHOM christopher d. WANJURA John d. PELLETIer Mathew G. HOLT Gregory A. HEQUET eric F. USdA-ARS New OrleansLA 70124USA USdA-ARS LubbockTX 79403USA Texas Tech University LubbockTX 79409USA

Background The strength of cotton fiber has been extensively studied and significantly improved through selec-tive breeding,but fiber elongation has largely been ignored,even though elongation contributes to determining the energy needed to break *** developments to calibrate the high volume instrument(HVI)for elongation has renewed interest in ***,it is not understood how best to utilize yet another fiber property which has the potential to add to the complexity of fiber *** explore a practical approach to applying elongation,cot-ton samples were tested using single fiber methods,the Stelometer,and the *** of strength,elongation,and combined properties such as modulus were *** HVI testing was shown to be sensitive enough to characterize elongation differences but unlike single fiber testing it was unable to capture within-sample *** bundle testing,like Stelometer and HVI was shown to reduce bias due to fiber *** The use of secant modulus,an intrinsic material property,allowed for one value to represent both strength and *** modulus was shown to contain more useful information than either elongation or ***-to-break was shown to be more influenced by a specific value of breaking force or elongation rather than the intrinsic behavior of the sample being *** the influence of genetics and environment on elongation,and its interaction with other fiber properties,requires additional *** modulus,by combining strength and elongation into one value,shows the potential to incorporate elongation values into fiber characteriza-tion without increasing the complexity of current fiber selection processes.

关键词： Cotton Elongation Tenacity Work-to-break ModulusBackground

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development of a CO_2 Tolerant Fischer-Tropsch Catalyst:from Laboratory to Commercial-Sca1e demonstration in Alaska

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Journal of Natural Gas Chemistry 2004年第1期13卷 1-9页

作者： Joep J H M Font Freide Tim d Gamlin J Richard Hensman Barry Nay christopher Sharp BP Exploration Operating Company Chertsey RoadSunbury on ThamesMiddlesexTWl6 7LNEnglandDavy Process Technology Lid 20 Eastbourne TerraceLondon W2 6LEEnglandDavy Process Technology Lid 20 Eastbourne TerraceLondon W2 6LEEnglandBP Chemicals LtdChertsey RoadSunbury on ThamesMiddlesexTW16 7LLEnglandBP Chemicals LtdChertsey RoadSunbury on ThamesMiddlesexTW16 7LLEngland

This article describes the development of BP's Fischer-Tropsch catalyst, used for the conversion of carbon monoxide and hydrogen into liquid hydrocarbons. It covers the 18 year period from the early eighties, when laboratory scale preparations and micro-reactors were heavily used, right through to the present day with the commercial scale manufacture and proving of the finished catalyst in BP's new ＄86 million gas to liquids demonstration facility in Nikiski, Alaska. Extensive performance testing and scale-up experiments have been successfully carried out, all proof that a laboratory preparation can indeed be translated into a commercial manufacturing process. In addition, the resulting catalyst does not only meet the process design targets, but also exhibits enhanced stability and is tolerant to carbon dioxide. Above all, a commercial scale, fixed bed Fischer-Tropsch catalyst is now available and ready for licensing. Manufacturing procedures and quality control have all been successfully detailed and transferred to the commercial manufacturer.

关键词： carbon dioxide Fisher-Tropsch development syngas commercial catalyst

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Metabolic dysfunction-associated fatty liver disease and hepatocellular carcinoma:present and future

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Hepatobiliary Surgery and Nutrition 2023年第6期12卷 945-948页

作者： Feng Gao Gang Chen christopher d.Byrne Giovanni Targher Tan To Cheung Ming-Hua Zheng department of Gastroenterology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhouChina department of Hepatobiliary Surgery The First Affiliated Hospital of Wenzhou Medical UniversityWenzhouChina Key Laboratory of diagnosis and Treatment of Severe Hepato-Pancreatic diseases of Zhejiang Province The First Affiliated Hospital of Wenzhou Medical UniversityWenzhouChina Hepatobiliary Pancreatic Tumor Bioengineering Cross International Joint Laboratory of Zhejiang Province The First Affiliated Hospital of Wenzhou Medical UniversityWenzhouChina Southampton National Institute for Health and Care Research Biomedical Research CentreUniversity Hospital Southampton and University of SouthamptonSouthampton General HospitalSouthamptonUK department of Medicine University of VeronaVeronaItaly IRCCS Sacro Cuore-don Calabria Hospital Negrar di ValpolicellaItaly department of Surgery Queen Mary HospitalThe University of Hong KongHong KongChina MAFLd Research Center Department of HepatologyThe First Affiliated Hospital of Wenzhou Medical UniversityWenzhouChina Institute of Hepatology Wenzhou Medical UniversityWenzhouChina Key Laboratory of diagnosis and Treatment for the development of Chronic Liver disease in Zhejiang Province WenzhouChina

Metabolic dysfunction-associated fatty liver disease(MAFLd),previously termed non-alcoholic fatty liver disease,is one of the most common causes of chronic liver disease,affecting around 30%of the world’s adults(1).MAFLd encompasses a spectrum of liver conditions,ranging from simple steatosis to metabolic dysfunction-associated steatohepatitis(MASH),which can progress to cirrhosis and hepatocellular carcinoma(HCC)(2,3).

关键词： Metabolic dysfunction-associated fatty liver disease(MAFLd) metabolic dysfunction-associated steatotic liver disease nonalcoholic fatty liver disease hepatocellular carcinoma(HCC) epidemiology

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Time-resolved, defect-hosted, trace element mobility in deformedWitwatersrand pyrite

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Geoscience Frontiers 2019年第1期10卷 55-63页

作者： denis Fougerouse Steven M.Reddy christopher L.Kirkland david W.Saxey William d.Rickard Robert M.Hough School of Earth and Planetary Sciences The Institute for Geoscience Research (TIGeR) Curtin University Geoscience Atom Probe Advanced Resource Characterisation Facility John de Laeter Centre Curtin University CSIRO Minerals Resources

The Pb isotopic composition of rocks is widely used to constrain the sources and mobility of melts and hydrothermal fluids in the Earth's crust. In many cases, the Pb isotopic composition appears to represent mixing of multiple Pb reservoirs. However, the nature, scale and mechanisms responsible for isotopic mixing are not well known. Additionally, the trace element composition of sulphide minerals are routinely used in ore deposit research, mineral exploration and environmental studies, though little is known about element mobility in sulphides during metamorphism and deformation. To investigate the mechanisms of trace element mobility in a deformed Witwatersrand pyrite(FeS_2), we have combined electron backscatter diffraction(EBSd) and atom probe microscopy(APM). The results indicate that the pyrite microstructural features record widely different Pb isotopic compositions, covering the entire range of previously published sulphide Pb compositions from the Witwatersrand basin. We show that entangled dislocations record enhanced Pb, Sb, Ni, Tl and Cu composition likely due to entrapment and short-circuit diffusion in dislocation cores. These dislocations preserve the Pb isotopic composition of the pyrite at the time of growth(~3 Ga) and show that dislocation intersections, likely to be common in deforming minerals, limit trace element mobility. In contrast, Pb, As, Ni, Co, Sb and Bi decorate a highangle grain boundary which formed soon after crystallisation by sub-grain rotation *** isotopic composition within this boundary indicates the addition of externally-derived Pb and trace elements during greenschist metamorphism at ~2 Ga. Our results show that discrete Pb reservoirs are nanometric in scale, and illustrate that grain boundaries may remain open systems for trace element mobility over 1 billion years after their formation.

关键词： Atom probe microscopy Nanoscale Nanogeochronology Microstructure Isotope geochemistry Common Pb

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Chronic hepatitis delta: A state-of-the-art review and new therapies

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World Journal of Gastroenterology 2019年第32期25卷 4580-4597页

作者： Christy Gilman Theo Heller christopher Koh Liver diseases Branch National Institute of Diabetes and Digestive and Kidney Diseases National Institutes of Health

Chronic delta hepatitis is the most severe form of viral hepatitis affecting nearly 65 million people *** with this devastating illness are at higher risk for developing cirrhosis and hepatocellular *** virus is a defective RNA virus that requires hepatitis B surface antigen for propagation in *** can occur in the form of a co-infection with hepatitis B,which can be self-limiting,vs superinfection in a patient with established hepatitis B infection,which often leads to chronicity in majority of *** noninvasive tools to assess for advanced liver disease have limited utility in delta *** recommend treatment with pegylated interferon,but this is limited to patients with compensated disease and is efficacious in about 30%of those *** to limited treatment options,novel agents are being investigated and include entry,assembly and export inhibitors of viral particles in addition to stimulators of the host immune *** clinical trials should take into consideration the interaction of hepatitis B and hepatitis d as suppression of one virus can lead to the activation of the ***,surrogate markers of treatment efficacy have been proposed.

关键词： Hepatitis delta Epidemiology Treatment

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Bioavailability of Arsenic and Antimony in Terrestrial Ecosystems:A Review

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Pedosphere 2019年第6期29卷 681-720页

作者： Saeed BAGHerIFAM Trevor CBROWN christopher MFELLOWS Ravi NAIdU Chemistry-School of Science and Technology University of New EnglandArmidale NSW 2351(Australia Global Centre for Environmental Remediation Faculty of Science and Inform ation TechnologyUniversity o f NewcastleUniversity DriveCallaghan N S W 2308(Australia

Arsenic (As) and antimony (Sb) are metalloids that belong to group 15 of the periodic table and exhibit toxic properties in the environment. They mostly occur naturally at low concentrations in soil, although these can be significantly elevated in both aquatic and terrestrial food chains as a result of dispersion from anthropogenic sources, e.g ., mining activities. The bioavailability, i.e., the proportion of the contaminant in soil and dust that is available for uptake by plants and other living organisms, presents the greatest risk to terrestrial ecosystems. Various in vivo and in vitro methods have been used to measure As and Sb bioaccessibility in soil and dust. In vivo measurement of bioavailability can be time consuming, expensive, and unethical;thus, in vitro methods are commonly preferred. However, there is considerable uncertainty around the efficacy of in vitro tools used to measure the bioavailable fractions of As and Sb. The results of these methods are dependent on many variables, e.g., soil characteristics, contaminant sources, and chemical composition of in vitro methods. Therefore, substantial variations are observed between in vitro and in vivo results obtained from different test animals and endpoints. In this paper, we review the literature on As and Sb bioavailability in terrestrial ecosystems and current in vivo and in vitro techniques used for assessing bioavailability and bioaccessibility of metalloids. This would reveal research gaps and allow scientists and environmental policy makers to gain a deeper understanding of the potential risks associated with these metalloids in the environment.

关键词： Bioaccessibility Bioavailable fraction Contamination Environmental risk assessment Metalloids Phytoavailability Relative bioavailability Soil characteristics Toxicant

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Improved hemostasis with major hepatic resection in the current surgical era

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Hepatobiliary & Pancreatic diseases International 2019年第5期18卷 439-445页

作者： christopher W Mangieri Matthew A Strode Bradley C Bandera department of Surgery Dwight D. Eisenhower Army Medical Center(DDEAMC)Fort GordonGA 30809USA department of Surgical Oncology Roswell Park Cancer InstituteBuffaloNY 14203USA

Background: Major hepatic resection, predominantly performed for oncologic intent, is a complex procedure with the potential for severe intraoperative hemorrhage. The current surgical era has the ability to improve hemostasis throughout the performance of major hepatic resections which decreases blood transfusions and the detrimental effects associated with transfusion. We evaluated hemostasis and outcomes in the current surgical era of performing hepatic resections. Methods: Utilizing the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database all major hepatic resections performed between 2012 and 2016 were analyzed in regards to hemostasis. Hemostasis was evaluated by the need for and magnitude of blood transfusions. Additional perioperative variables (including operative time, length of hospital stay, and mortality rates) were analyzed to assess for outcomes with hemostasis. The NSQIP results were compared to previous publications involving major hepatic resections to detect improvement in hemostasis and outcomes in the current surgical era. Results: A total of 22777 major hepatic resections met the inclusion criteria for analysis in the NSQIP database. An additional 21198 cases were compiled within the selected publications for comparative analysis. The transfusion rate in the current surgical era was 13.3% versus 38.7% in the previous era ( P = 0.0001). When a transfusion was required in the current surgical era there was a two-fold reduction in the number of units transfused (1.5 U vs. 3.8 U, P = 0.0001). Statistically significant improvements in operative time and length of hospital stay were presented within the current surgical era ( P = 0.0001). When a transfusion was required there was an increased relative risk score of 7 for mortality (4.9% vs. 0.7%, P = 0.0001), however, improvement in mortality rates did not reach statistical significance across surgical eras (1.3% vs. 4.0%, P = 0.0001). Conclusions: The cond

关键词： Major hepatic resection Improved hemostasis Improved outcomes

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Updating digital elevation models via change detection and fusion of human and remote sensor data in urban environments

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International Journal of digital Earth 2015年第2期8卷 153-171页

作者： Carolin Klonner christopher Barron Pascal Neis Bernhard Hofle department of Geography University of HeidelbergHeidelbergGermany

OpenStreetMap(OSM)currently represents the most popular project of Volunteered Geographic Information(VGI):geodata are collected by common people and made available for public *** Laser Scanning(ALS)enables the acquisition of high-resolution digital elevation models that are used for many *** study combines the advantages of both ALS and OSM,offering a promising new approach that enhances data quality and allows change detection:the mainly up-to-date 2d data of OSM can be combined with the high-resolution–but rarely updated–elevation information provided by *** case study investigates building objects of OSM and ALS data of the city of Bregenz,*** quality of OSM is discerned by the comparison of building footprints using different true positive definitions(*** area).High quality of OSM data is revealed,yet also limitations of each method with respect to heterogeneous regions and building outlines are *** the first time,an up-to-date digital Surface Model(dSM)combining 2d OSM and ALS data is achieved.A multitude of applications such as flood simulations and solar potential assessments can directly benefit from this data combination,since their value and reliability strongly depend on an up-to-date dSM.

关键词： OpenStreetMap airborne laser scanning change detection 3d modelling up-to-date digital surface models

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Improved bridge pier collar for reducing scour

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International Journal of Sediment Research 2022年第1期37卷 37-46页

作者： christopher Valela Colin david Rennie Ioan Nistor department of Civil Engineering University of Ottawa

This study performed a bridge pier collar comparison for the purpose of reducing scour,while introducing a new collar *** new collar,referred to as Collar Prototype Number 3,was designed based on an equilibrium scour hole and provides a method of controlling the horseshoe *** modelling was utilized to show the flow field and bed shear stress as a result of using Collar Prototype Number 3.A prototype model of Collar Prototype Number 3 and a flat plate collar were constructed for the purpose of comparing both experimentally under different flow *** Prototype Number 3 proved to be an effective device as it reduced scour in terms of the maximum depth downstream of the pier and overall volume,in some instances,by up to 69.7%and 75.7%,***,Collar Prototype Number 3 outperformed the flat plate collar,especially because,unlike the flat plate collar,Collar Prototype Number 3 did not experience undermining.

关键词： Bridge pier Scour Horseshoe vortex Pier collar Scour countermeasure

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